Note 5 - Loans and Allowance for Loan Losses - Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Number of loans	6	7
Pre- modification outstanding principal balance	$ 541	$ 594
Post- modification principal balance	$ 214	$ 297
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member]
Number of loans	1	1
Pre- modification outstanding principal balance	$ 107	$ 107
Post- modification principal balance	$ 71	$ 73
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Number of loans	3	3
Pre- modification outstanding principal balance	$ 318	$ 318
Post- modification principal balance	$ 74	$ 118
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member]
Number of loans		1
Pre- modification outstanding principal balance		$ 53
Post- modification principal balance		$ 34
Commercial and Industrial Loans [Member]
Number of loans	2	2
Pre- modification outstanding principal balance	$ 116	$ 116
Post- modification principal balance	$ 69	$ 72

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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